Oxide nanoparticles are the subject of intense research efforts due to the wide variety of applications for which they are suited. Nanometer sized oxide particulates have been used in a wide variety of applications: electronic and magnetic devices, energy storage and generating systems and even medical applications. In general, there is a myriad of different synthetic techniques depending on the type of particle being prepared.
However, none of these techniques have demonstrated broad-spectrum applicability for oxide nanoparticle synthesis. The prior art techniques only produce micrograms of material.
Nanometer sized oxide particles were first considered theoretically in the mid 1980's, and synthesized a few years later. One of the first uses for metal oxide nanoparticles was Fe2O3 nanoparticles (≈50 nM) in magnetic data storage. Since that time, numerous other applications have been developed such as the Gretzel Solar cell, which uses dye-coated TiO2 particles to absorb incident radiation. Additionally, metal oxide nanoparticles have been explored as high-energy cathode materials for lithium batteries.
The critical performance aspect of these nanoparticles relates to their very small size, which corresponds to increased surface area.
As a general rule, this reduction in size and increase in surface area significantly increase the desired interactions either by enhancing energy adsorption in the Gretzel cell, or increasing the amount and rate at which Li+ can be intercalated and de-intercalated into the cathode.
Additionally, nanoparticles in general allow for new and varied approaches to creating nanometer to micron sized electrical components by creating transferable inks of these nanometer-sized particles. These techniques, such as laser printing, laser direct write printing, and 3-d printing take advantage to two key features of nanoparticles: small size allows for great flexibility and compactness in component design. The very small size of the particles also results in far greater reactivity. As such, annealing of an ink such as one composed of nanoparticulates of CeO2 can create stable ceramic films at temperatures well below the melting point of CeO2.
Unfortunately, one of the greatest problems facing the production of oxide-based nanoparticulates is the difficulty in rapidly synthesizing significant quantities of material. Typically, production requires several different steps to control particles size and to coat the nanoparticles to prevent them from aggregating, resulting in increasing particle size over time. These syntheses result in the formation of only micrograms of the oxide nanoparticulates.